Marine working platform substructure



- Aug. 6, 1940. c. HENRY MARINE wonxme PLATFORM SUBSTRUGTURE 3 Sheets-Sheet 1 Filed Sept. 8, 1938 A, ATTORNEYS.

I WITNESSES g- 5, 1940- c. L. HENRY 2210, 0

MARINE WORKING PLATFORM SUBSTRUCTURE Filed Sept. 8, 1938 s Sheets-Sheet 2 wlrwtssis INVENTOR.

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Aug.6, 1940. ,HE Y 2,210,408

MARINE WORKING PLATFORM SUBSTRUCTURE Filed Sept. 8, 1938 3 Sheets-Sheet 3 I INVENTOR. M444 W/TNEJJEJ BY macaw 71%. 4 ATTORNEYS.

Patented Aug. 6, 1940 I UNITED sirA'rEs az oaoa MARINE Woaxma suns'rrwcmn Charles 'L. Henry, Pittsburgh, Pa., Mm, to Lee 0. Moore & Company, Inc., Pittsburgh, Pa., a corporation of Pennsylvania.

Application September 8,1938, Serial No. 228,953 Giaims. (cl. 61- 6) This invention relates to drilling derricks, such as oil well derricks, and more particularly to derrick structures for drilling under dies of water.

Considerable drilling, especially for oil wells, is

5 done under bodies of water, such as inthe beds of lakes, bays or oceans. sive, especially when the water is deep, to construct a foundation for a working platform and superstructure in the usual way by driving piles or making concrete piers. In rough water or where the tide fluctuates greatly it is practically impossible to form a derrick support imthis manner, because the work must be carried on from the surface of the water which rises and falls.

1 It is among the objects of this invention to provide a method of erecting a working platform for a derrick over a body of water which can be carried out satisfactorily in spite of rough or deep water, and which is relatively simple and inexpensive to practice. @ther objects are to provide a derrick structure for use in drilling in the beds of bodies of water which can be lowered through the water and onto the bed at the drilling site without appreciable difficulty and without the 25 use of piles or piers, regardless of theaction of the surface of the water.

In accordance with this invention a working platform and at least part of its substructure are constructed on land and the substructure is mounted on caissons. This structure is then carried by a barge or the like to the drilling site and the substructure and caissons are lowered through the water until the caissons rest on bottom. The caissons are jetted down to a firm foundation in order to support the platform above the water. If only apart of the substructure is assembled on land, it is completed at the drilling site as the caissons are lowered. On the other hand, if it is completed on land, the superstruc- 40 ture above the working platform may likewise be erected at the same time if desired.

The invention is illustrated in the accompanying drawings in which Fig. 1 is 'a side view of a working platform supported over a body of water by a substructure; Fig. 2 is a plan view of the platform showing the corner towers as viewed on the line IIII of Fig. 1; Fig. 3 is a side view of the platform supported by a barge and carrying partially assembled corner towers; Fig. 4 is an enlarged fragmentary section taken on the line IVIV of Fig. 3; Fig. 5 is a side view of a modified embodiment of this invention; and Fig. 6 is an enlarged vertical section of the supporting structure for one of the derrick legs.

Referring to Figs. 1 and 2 of the drawings, a

It is difficult and expenplurality of metal towers I are mounted vattheir lower ends on caissons 2. which serve as spread footings therefor and support the towers on the bed 3 of a body of water 4. Each tower is a structural steel unit formed from vertical columns 6 connected together by girts and braces. The towers extend above the water and support a working platform 6 sufficiently far above it to be unafthe platform and to the sides of the towers below 20 Another feature if this invention is that working platform 6 is transported to the drilling site by a 'barge i I (Fig. 3) on which it is supported by jacks l2. During this movement of the platform the towers are only partially assembled, there being only the short bottom section of each tower mounted on each caisson 2 and extending through each corner of the platform. Due to the air in the caissons they are rendered buoyant and support the tower sections in the platform. If desired, the tower sections may be temporarily secured to the platform. When the barge reaches the drilling site the height of the towers is increased by adding structural members to their upper ends above the platform. Preferably, the members are prefabricated into short sections so that a section at a time: can be added, thereby requiring less work to be done over the water. This work is facilitated by means of a gin pole 40 .I3 or the like mounted on the barge. As the height of the towers is increased the added weight sinks the caissons down through the water until they rest on bottom.

To assure the caissons of resting on a firm foundation below mud or loose sand, and to permit the tops of the towers to be disposed in sub stantially the same horizontal plane, means is provided for jetting out the caissons so as to remove loose material from them and permit them to settle. Preferably, for this purpose a vertical pipe I 4 is disposed in each tower with its lower end opening into the underlying caisson. The upper end of the pipe is adapted to be connected to a source of fluid under pressure (not shown), 5!

. or otherwise secured to the towers.

preferably both air and water, whereby the buoy-- ancy of the caisson can be controlled and mud can be jetted out from it after it reaches bottom. The pipe is provided with any suitable check valve (not shown) so that air within the caisson can not escape upwardly through the pipe. Each pipe may be assembled in sections. of the same length as the tower sections as the tower is assembledu By controlling the volume of air in the caissons tic equilibrium of the barge can be preserved while the towers are being erected.

Asshown in Fig. 4, the towers are guided, as they are lowered, by vertical angle irons I connected to the platform. After the towers have,

. jacks l2 are used for raising or lowering the plat- 'form to proper position for fastening to the towers, after which they are lowered to free the barge from the platform so that the barge can be towed away, leaving the platform flrmly supported by the towers which are ready to receive the derrick.

In the embodiment illustrated in Figs. 5 and 6 the substructure for the working platform 2! consists principally of the lower part 22 of the derrick itself, the superstructure 29 above the platform being the upper portion of the derrick. In other words, the working platform is disposed at the desired level in a derrick, the lower portion of which is adapted to extend down through a body of water 24. In accordance with this invention, each leg 26 of the derrick is mounted on a caisson 21 which supports the derrick on the bed 28 of the body of water. The'derrick is preferably completely constructed on land where it is mounted on the caissons. It is then towed between barges to the drilling site at which it is lowered through the water until the caissons rest on bottom.

It is a feature of this invention that working platform 2| can be brought into a substantially horizontal plane, even though bed 28 is irregular, by independently raising or lowering each derrick leg relative to its underlying caisson. Accordingly, each leg is connected to its caisson by a jack 3| which is operable from above the water. Preferably, the bottom of each leg is connected to the upper end of a tube 32 which telescopes over another tube 33 connected to the caisson below it. Rigidly mounted in the lower tube is an internally threaded nut. 34 (Fig. 6) in which the lower portion of a jack screw 36 is threaded. The upper end of this screw bears against the bottom of the derrick leg through a thrust bearing 31 and is rotatable by a pipe 33 that extends upwardly through the tubular leg of the derrick to the top of the derrick where any suitable means (not shown) may be employed for turning the pipe. When the pipe is turned, the jack screw raises the leg or permits it to descend relative to the lower telescoping tube of the jack. The bottom of lower tube 33 is preferably connectedto a fluld under pressure, and each jack screw and universal joint ballare provided with axial bores. The fluid under pressure, such as water, can thus be forced down through the pipes, jacks and balls and into the caissons, the lower edges of which are sharpenedto aid them in settling through the mud.

With either embodiment of this invention the working platform and at least a part of its substructure can be constructed on land. The platform can then be relatively quickly erected over the drilling site in a simple manner. This can be done regardless of whether the water is rough or whether the tide rises and falls a great amount, because the work is not carried on in connection with stationary objects, such as piles or piers. That is, the entire drilling structure floats in the water until the caissons reach bottom, so the condition of the surface of the water is of little importance. After that there is little to do to complete the setting of the platform. The modification shown in Figs. 5 and 6 can be set at the drilling site even more quickly than the first embodiment, although it is not as suitable for very deep water as the tower substructure type. Another advantage of this invention is that the entire drilling structure can be raised and moved to another location in case that is desirable without leaving an expensive foundation at the original site.

According to the provisions of the patent statutes, I have explained the principle and construction of my invention and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

I claim:

1. The method of erecting a working platform over a body of water, comprising supporting the platform on a barge, floating the barge on the water to the desired location, slidably'mounting a tower in each corner portion of the platform, mounting the lower end of each tower on a caisson, increasing the height of each tower at the drilling site by adding to its upper end, lowering the towers through the platform and water as their height is increased until the caissons rest on bottom, jetting out the caissons to permit them to settle and rest on firm bottom, jacking up the platform on the barge to raise it above the water, fastening the platform to the towers, and then floating the barge out from under the platform.

2. A structure for supporting a derrick over a body of water, comprising a working platform provided with a plurality of vertical openings, a tower extending through each of said openings and supporting the platform, said towers being slidable vertically through said openings when disconnected from the platform, a caisson mounted on the lower end of each tower, and means for jetting out the caissons.

3. A structure for supporting a derrick over a body of water, comprising 'a working platform provided with a plurality of vertical openings, a tower extending through each of said openings and supporting the platform, a caisson mounted on the lower end of each tower, the upper ends of the towers being adapted to support the legs of a derrick, and a vertical pipe disposed in each tower and communicating at its lower end with the inside of the underlying caisson, the upper end of each pipe being adapted to be connected 5. A supporting structure for use in a body of to a source of fluid under pressure. water, comprising a platform adapted to be dis- 4. The method of erecting a platform over a posed over the water and provided with a plubody of water comprising supporting the platrality of vertical openings therethrough, a tower 5 form on a barge, floating the barge on the water extending through each of said openings and 5 to the desired location, slidably mounting a verdownwardly from the platform, each tower being tical tower in said platform, mounting the lower adapted to have its height increased for use in end of the tower on a supporting member, indeeper water, the horizontal cross section of each creasing the height of the tower by adding to its tower being so small that the tower would be 10 upper end, lowering the tower through the plat likely to sink into the bed of said body of water, 10

form and water as its height is increased until a spread footing member mounted on the lower said supporting member rests on bottom, jackend of each tower to restrain it from sinking, and ing up the platform on the barge to raise it above means for detachably comlecting the towers to the water, fastening the tower to the platform for the platform for supporting it.

is rigidly supporting the latter, and then floating 15- the barge out from under the platform. CHARLES L. HENRY. 

